Visual indicator for aircraft radio beacon systems



May 12, 1936.

1. J. GALLAGHER 2,040,734

VISUAL INDICATOR FOR AIRCRAFT RADIO BEACON SYSTEMS Filed April 5, 1933 Invenlar .Ziwzky e7." faZZg/zer f1 llorney imam! May 12, 1936 UNITED STATES;

- amass vr suar. mmca'roa ro'a masr'r aanro moon sits-r ms Irving J. suntan, N. r. 7 Application Alll'll 5.1m, Serial No. mass This invention appertains to new and useful improvements in tuned reed indicators. for use in connection with radio beacon systems; the

present invention aiming to increase the efii-' ciency of the present types of reed indicators by adding visual means in the form of signal lamps which are controlled-by the action of the reeds of the conventional reed indicator.

The conventional timed reed indicator is a tion with the radio beacon system'for guiding aircraft. This beacon system was developed with a view to giving a pilot an indication as to whether or not he is flying on a specified course, and if not, to which'side and how much he has deviated. This indication is given by two vibrating reeds, the relative amplitudes of vibration of which indicate theposition of the aircraft with respect to the beacon course. Equal amplitude of the two reeds indicates that the airplane is on the course. The reeds give a continuous indicationto the pilot of his position with respect to his course. This indication is obtained without much difficulty by the pilot, but when flying through fog, the pilot is bound to carefully watch the reeds and this results in considerable eye strain. I It is, therefore, an importantobject of the "present invention to provide a visual indicator 30 in the forng, of a directional signal outfit which will give the direction of flight in a clear and well defined manner, and which will eliminate the necessity of the pilot keeping hiseyes fixed on the instrument for any tiring length of time.-

Another important object of the invention is to provide a course indicator of the type above specified which'employs an "on course" signal and "off course signal, wherein the "off course signal will become deenergized and V the "on course'f signal singly energized when the aircraftisdirectiyonitscourse. I f 1 These and'variousother important objects and advantages of the inventiorrwill become. apparent to the reader of the following specification.

In the drawing:- g

Figure l nepresents a diagrammatic view of the invention, theesameshowing the electrical elements-employed and the connectionsibetween thesame. 50 Figure z-represents a fragmentary front elevational=view of the instrument board of an aircraft, showing the direction signal box installed thereon. Referring to the wherein like numeralsdesignatelikeparmit'canbeseenthat simple and reliable instrument for use in conneclClairn. (Cl. 171-352) numerals 8-8 represent the' tuned reeds, each operated by a pair of electromagnets "I--I on a permanent-horseshoe magnet I. These magnets I are bridged by the jumper a.

Arbitrarily, the reed i is tuned for-approxi- 5 mately 65 cycle vibrations, while the reed B is V tuned for approximately 86.7 cycle vibrations. As in conventional hook-ups, the-output 9 of the beacon receiver is connected to the coils 1-1 in the manner substantially shown in Figure 1,

In "carrying out the present invention, a contact II is placed on each side of each of the reeds 5-6. Numeral ll represents the left 'off course light circuit which-includes the signal lamp l2 and its source of current It, while numeral ll 15 represents the right "of! course signal circuit which includes the signal lamp l5 andsource of currentli.

' Each of these circuits H and I4 has amagnetically operated switch generally referred to 20 by numeral I! installed therein and as is clearly shown in Figure 1, a pair of contacts lll- -IO is ,located in this circuit. A connection I8 is providedbetween the coils I! of the electro-magnetic switches l1 and in this connection is the 2 on course signal lamp 20 and its source ofcurrent 2|.

In operation, assume that the aircraft is off its coufse on the left of the beacon. The reed 5 will vibrate and in engaging the contacts III, will close the circuit Ii to the end that the lamp l2 will be energized and will indicate to the pilot that he is oil the course on the left. While the lamp I2 is energized, the lamp I5 is, of course, de-energined because of the inactivity of the reed 6.

' The same operation takes placewhen the aircraft is on the right of the beacon, in which case the circuit I4 is energized for lighting the lamp ii. a

When the aircraft returns to the course, both of the reeds will operate simultaneously, which 40 will result in the energization of the electro-magnets l9, opening the switches, thus breaking the lamp circuits II and II and adopting part of these circuits to form a circuit for the "on course" lamp 20 which will now be energized.

It is preferable that the lamps l2 and I as well as the lainp II he installed ina lamp box 22 situated on the usual instrument board 23 of the aircraft and it is furthermore desirable that.

commodate the three lamps hereinbefore specifled.

'lhusitcanbeseenthatthereedsareentircly invisible to the pilot and that the pilot will de- 5 pend upon the clearer and more well deilned form oi. indication oirered by the lamps.

I While the foregoing specification sets forth the Having described the invention, what is claimed as new is:

means.

In a radio aircraft beacon indicator, a pairot vibratory armature relays having normally separated contacts, and tuned to diilerent trequenq cies of vibration, .a second pair of relays, having contacts in normally closed circuit position, a

.circuit to be controlled by eachot the vibratory ing a'signal, a source of current, the magnets oi the; second relays and contacts of the vibratory I relays in series.

IRVING J. QAILAGHER. 

